The present invention pertains to inter-processor communication and more particularly to data collision detection and recovery in multi-processor communication systems.
In distributed control systems, a number of processors perform portions of the overall operation of a functional unit, such as a telephone, for example. Modern telephones are sophisticated devices which provide for a number of features such as security. In addition, such phones provide for interfacing with facsimile machines, copying machines and other telecommunication devices. The processors which control these different functions must communicate with one another. Typically, these processors are interconnected by a bus. This bus may be a serial bus and employ a CARRIER SENSE MULTIPLE ACCESS WITH COLLISION DETECTION (CSMA/CD) bus protocol.
These multi-processor communication systems do not detect data collisions on the bus under all conditions. Further, such systems do not provide an efficient arrangement for settling conflicts between processors involved in a data collision.
Accordingly, it is highly desirable to provide a multiple processor communication system which detects data collisions under all conditions and resolves the collisions by efficiently permitting processors to communicate in a prioritized fashion.